.. program:: pt-pmp
=================
:program:`pt-pmp`
=================
NAME
====
:program:`pt-pmp` - Aggregate GDB stack traces for a selected program.
SYNOPSIS
========
Usage
-----
::
pt-pmp [OPTIONS] [FILES]
:program:`pt-pmp` is a poor man's profiler, inspired by `http://poormansprofiler.org `_.
It can create and summarize full stack traces of processes on Linux.
Summaries of stack traces can be an invaluable tool for diagnosing what
a process is waiting for.
RISKS
=====
The following section is included to inform users about the potential risks,
whether known or unknown, of using this tool. The two main categories of risks
are those created by the nature of the tool (e.g. read-only tools vs. read-write
tools) and those created by bugs.
:program:`pt-pmp` is a read-only tool. However, collecting GDB stacktraces is achieved by
attaching GDB to the program and printing stack traces from all threads. This
will freeze the program for some period of time, ranging from a second or so to
much longer on very busy systems with a lot of memory and many threads in the
program. In the tool's default usage as a MySQL profiling tool, this means that
MySQL will be unresponsive while the tool runs, although if you are using the
tool to diagnose an unresponsive server, there is really no reason not to do
this. In addition to freezing the server, there is also some risk of the server
crashing or performing badly after GDB detaches from it.
At the time of this release, we know of no bugs that could cause serious harm
to users.
The authoritative source for updated information is always the online issue
tracking system. Issues that affect this tool will be marked as such. You can
see a list of such issues at the following URL:
`http://www.percona.com/bugs/pt-pmp `_.
See also "BUGS" for more information on filing bugs and getting help.
DESCRIPTION
===========
:program:`pt-pmp` performs two tasks: it gets a stack trace, and it summarizes the stack
trace. If a file is given on the command line, the tool skips the first step
and just aggregates the file.
To summarize the stack trace, the tool extracts the function name (symbol)
from each level of the stack, and combines them with commas. It does this
for each thread in the output. Afterwards, it sorts similar threads together
and counts how many of each one there are, then sorts them most-frequent first.
OPTIONS
=======
Options must precede files on the command line.
-b BINARY
Which binary to trace (default mysqld)
-i ITERATIONS
How many traces to gather and aggregate (default 1)
-k KEEPFILE
Keep the raw traces in this file after aggregation
-l NUMBER
Aggregate only first NUMBER functions; 0=infinity (default 0)
-p PID
Process ID of the process to trace; overrides -b
-s SLEEPTIME
Number of seconds to sleep between iterations (default 0)
ENVIRONMENT
===========
This tool does not use any environment variables.
SYSTEM REQUIREMENTS
===================
This tool requires Bash v3 or newer.
BUGS
====
For a list of known bugs, see `http://www.percona.com/bugs/pt-pmp `_.
Please report bugs at `https://bugs.launchpad.net/percona-toolkit `_.
Include the following information in your bug report:
* Complete command-line used to run the tool
* Tool :option:`--version`
* MySQL version of all servers involved
* Output from the tool including STDERR
* Input files (log/dump/config files, etc.)
If possible, include debugging output by running the tool with ``PTDEBUG``;
see "ENVIRONMENT".
DOWNLOADING
===========
Visit `http://www.percona.com/software/percona-toolkit/ `_ to download the
latest release of Percona Toolkit. Or, get the latest release from the
command line:
.. code-block:: bash
wget percona.com/get/percona-toolkit.tar.gz
wget percona.com/get/percona-toolkit.rpm
wget percona.com/get/percona-toolkit.deb
You can also get individual tools from the latest release:
.. code-block:: bash
wget percona.com/get/TOOL
Replace ``TOOL`` with the name of any tool.
AUTHORS
=======
Baron Schwartz, based on a script by Domas Mituzas (`http://poormansprofiler.org/ `_)
ABOUT PERCONA TOOLKIT
=====================
This tool is part of Percona Toolkit, a collection of advanced command-line
tools developed by Percona for MySQL support and consulting. Percona Toolkit
was forked from two projects in June, 2011: Maatkit and Aspersa. Those
projects were created by Baron Schwartz and developed primarily by him and
Daniel Nichter, both of whom are employed by Percona. Visit
`http://www.percona.com/software/ `_ for more software developed by Percona.
COPYRIGHT, LICENSE, AND WARRANTY
================================
This program is copyright 2010-2011 Baron Schwartz, 2011-2012 Percona Inc.
Feedback and improvements are welcome.
THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, version 2; OR the Perl Artistic License. On UNIX and similar
systems, you can issue \`man perlgpl' or \`man perlartistic' to read these
licenses.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA.
VERSION
=======
:program:`pt-pmp` 2.0.5